Memory Test

Technical Activity Committee on Memory Test

TAC Chair:  Yervant ZORIAN, y.zorian@computer.org

This technical area has been active with test community for over 30 years. Memory devices have traditionally been used as test vehicles for new technology, process monitoring and even design concepts. To provide a semi-formal forum to technologists and practitioners Memory Test TAC initiated an international workshop in 1993. This annual workshop, IEEE International Workshop on Memory Technology, Design and Testing is held annually during summer [1].

The primary scope of Memory TAC is testing and reliability of stand-alone and embedded memories. In addition, Memory TAC works together with other Technical Committees such as TC on VLSI within the Computer Society and other societies such as Solid State Circuits Society within the IEEE. This cooperation is reflected on MTDT, the scope of which expands from fabrication technology, memory design, testing and reliability. However, Memory TAC within TTTC primarily encourages testing and reliability aspects.

Testing of embedded memories has become one of the most important topics in last couple of years. The main problem is that multi-mega bits memory takes large test time on logic testers, on top of that the direct access to the memory itself is not available. The hardware overhead and performance penalty restricts the use of built-in self-test.

As embedded memories and standard components have different testing requirements. Since 1998, International Test Conference (ITC) has also recognized to address them separately. To properly cover this topic, each year two separate sessions have been devoted to memory testing, one on test generation and algorithm and other on embedded memories. In June 2001, IEEE Design and Test of Computers has also published an special issue on this topic.

Other major test topics encouraged by this TAC are:

  • Testing for commercial and space applications
  • What are the best test algorithms, the associated cost
  • How can a test algorithm be implemented on desktop and on tester to generate the patterns
  • What are available built-in self-test methods, their associated costs and benefits
  • Memory redundancy analysis and Built-in self-repair methods
  • Application of any particular test method, failure analysis and repair method
  • How to choose a memory test method for a given situation
  • How to predict storage and life-time reliability

References

  1. Records of IEEE Int. Workshop on Memory Technology, Design and Testing, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000 and 2001 Published by the IEEE Computer Society Press.